Weather maps
simply and graphically depict meteorological conditions in the atmosphere. Weather maps may display only one feature of the atmosphere or multiple features. They can depict information from computer models or from human observations.

On a weather map, important meteorological conditions are plotted for each weather station. Meteorologists use many different symbols as a quick and easy way to display information on the map (
Figure
below
).

Explanation of some symbols that may appear on a weather map.

Once conditions have been plotted, points of equal value can be connected by isolines. Weather maps can have many types of connecting lines. For example:

Lines of equal temperature are called
isotherms
. Isotherms show temperature gradients and can indicate the location of a front. In terms of precipitation, what does the 0
o
C (32
o
F) isotherm show?